From Software

Avoid the messy and painful flood of emails trying to set up a meeting!  These services enable flexible web-based scheduling, which can include one or both of simple ad-hoc meetings that don't require registration and client appointment setting.  Most are free with a premium service level.

Commentary

My ideal service is free, has meeting confirmation and reminders, works for both group and personal meetings, lets you set multiple schedules for different groups, has both a manual calendar and imports external calendars, and allows you to specify appointment time per schedule.  I currently use Thunderbird Lightning for my schedule, but also have Google Calendar.  I'm still looking for it!

Services

Includes both book on your calendar and asynchronous scheduling services. 

• Calendly
• Doodle (recommended, scheduling leader, requires external calendar)
• Google Calendar
• Meet-O-Matic
• Need to Meet
• Schedule Once. No free service. $5-9 for reminders, automatic booking
• SuperSaaS (recommended, for manual calendar, complex but lots of features)
• When is Good
• X.ai

Deadpool

C'ya!

• Arrange.cc
• Flexvite
• Meeting Wizard
• Time to Meet 
• Touchbase
• Tungle
• You can book me